What safety measure should be taken before performing maintenance on agricultural equipment?

The correct choice emphasizes the critical safety measure of disconnecting the power source and ensuring that the equipment is in a stable position before performing maintenance. This is fundamental because it helps prevent accidental activation of the machinery, which could result in serious injury or death. Equipment must be completely powered down, and energy sources, such as electrical connections or hydraulic systems, should be disconnected to protect the technician working on the machine.

Stabilizing the equipment further reduces the risk of it moving unexpectedly during maintenance activities. This is especially important for heavy agricultural machinery that may shift or roll if not properly secured. By adhering to this safety measure, technicians greatly enhance their protection against potential hazards while performing necessary maintenance tasks.

The other options, while important in their own right, do not address the primary concern of ensuring safety through power disconnection and stability, which are essential to create a safe working environment.